Alaskan Earthquake

                Alaska is currently commemorating the fiftieth anniversary of the 1964 earthquake  that struck at 5:36 p.m. on Good Friday, March 27, 1964.  It was a “mega thrust earthquake” that lasted for nearly three minutes.  It caused ground fissures, collapsing structures, and tsunamis across south-central Alaska; it also caused approximately 139 deaths.  It was the “most powerful recorded earthquake in U.S. and North American history, and the second most powerful ever measured by seismograph” and had “a moment magnitude of 9.2, making it the second largest earthquake in recorded history – the largest being the 1960 Valdivia earthquake in Chile.  It is known by various names:  1964 Alaskan Earthquake, the Great Alaskan Earthquake, the Portage Earthquake, and the Good Friday Earthquake.”

                Most of the soil in Anchorage and Alaska tends to liquefy during earthquakes, but this liquefaction mainly caused problems along the coasts where the liquid mud could spill into the ocean.  Several communities suffered much damage to property as well as landslides.  “Anchorage sustained great destruction or damage to many inadequately earthquake engineered houses, buildings, and infrastructure (paved streets, sidewalks, water and sewer mains, electrical systems, and other man-made equipment), particularly in the several landslide zones along Knik Arm.  Two hundred miles southwest, some areas near Kodiak were permanently raised by 30 feet (9.1 m).  Southeast of Anchorage, areas around the head of Turnagain Arm near Girdwood and Portage dropped as much as 8 feet (2.4 m), requiring reconstruction and fill to raise the Seward Highway above the new high tide mark.

                “In Prince William Sound, Port Valdez suffered a massive underwater landslide, resulting in the deaths of 30 people between the collapse of the Valdez City harbor and docks and inside the ship that was docked there at the time.  Nearby, a 27-foot (8.2 m) tsunami destroyed the village of Chenega, killing 23 of the 68 people who lived there; survivors out-ran the wave, climbing to high ground.  Post-quake tsunamis severely affected Whittier, Seward, Kodiak, and other Alaskan communities, as well as people and property in British Columbia, Oregon, and California.  Tsunamis also caused damage in Hawaii and Japan.  Evidence of motion directly related to the earthquake was reported from all over the earth.”

                There were about 139 people who died as a result of the earthquake and its after effects although only 15 died from the earthquake itself.  The resulting tsunami took 106 lives in Alaska, 5 in Oregon, and 13 in California.  Property damage from the earthquake has been estimated to be approximately $311 million or $2.28 billion in today’s dollars.

                The epicenter of the earthquake was 75 miles (120 km) southeast of Anchorage.  The tsunami did not hit Anchorage, but the downtown area of the city suffered heavy damage from the quake.  The Turnagain neighborhood suffered severe damage.  It is located on the sandy bluffs overlooking the “Bootlegger Cove” near Cook Inlet.  The clay soil in this area became liquefied, similar to melting Jell-O, and destroyed 75 houses; at least two houses slid toward the water.  One family lost two children in this area:  one child was lost when the ground opened up and closed again and the other was taken by the mudslide.  The area that was destroyed is now Earthquake Park.

                The Government Hill also suffered a landslide; this landslide caused the Government Hill School to break into two jagged, broken pieces.  Downtown Anchorage lost many acres of buildings and city blocks when the land overlooking the Ship Creek valley (near where the Alaska Railroad yards are located) slid down the hill.  There was moderate damage in most other areas of the city.  One person was killed when the 60-foot tall concrete control tower at the Anchorage International Airport collapsed.

                Girdwood and Portage are located about 30 and 40 miles (60 km) southeast of central Anchorage on the Turnagain Arm of Cook Inlet.  Both communities were destroyed; Portage was abandoned but Girdwood was moved away from the water and is home of Alyeska Ski Resort.  About twenty miles of the Seward Highway sank below the high water mark.  The highway and several bridges were raised and rebuilt in 1964-66.

                The seismic activity of the earthquake, tsunamis and/or fires heavily damaged most of the coastal towns located in the Prince William Sound or on the Kenai Peninsula and Kodiak Island.  The ports of Seward, Whittier and Kodiak were heavily damaged.  Valdez, not totally destroyed, moved to higher ground three years after the earthquake; it is now located about four miles west of its original site.  Native villages, including Chenega and Afognak, were destroyed or damaged.

                Prince Rupert, British Columbia, located south of the Alaska Panhandle, was hit by a 4.5 foot wave about three hours after the earthquake.  This tsunami then hit Tofino on Vancouver Island and went up a fjord to hit Port Albern – not once but twice; the water washed away 55 homes and damaged 375 more.  Other Canadian downs receiving damage were Hot Springs Cove, Zeballos, and Amai. 

                The tsunami also hit the Oregon and California coasts as well as other towns along the U.S. Pacific Northwest and Hawaii.  Boats were damaged in Los Angeles and tide gauges in Freeport, Texas, recorded waves similar to seismic surface waves.

                Thousands of aftershocks continued for approximately three weeks after the huge quake with eleven recorded on the first day with a magnitude greater than 6.2.  There were nine more aftershocks over the next three weeks.

                My family did not move to Alaska until 1973.  By that time most of the damage had been repaired and the only signs of the monster quake were Earthquake Park in Anchorage and water surrounding parts of buildings where Portage once stood.  I have many friends who were here during the earthquake who share their experiences with me.  It was by all reports a terrible experience!

                Alaska continues to experience many earthquakes.  In fact, we may experience four out of every five earthquakes in the nation!  Most of the buildings erected since 1964 have been built to earthquake standards.  Some of the original owners of land in the Turnagain area of Anchorage have petitioned the city for their property in order to rebuild in the area.  Many people who are purchasing already-built homes or building new homes have the soil in the area tested.  My home is located closer to the mountain on land filled with rocks.  I am hoping that my land will not liquefy in an earthquake, but I do have earthquake insurance - grandfathered in since it is impossible to purchase now. 

                The mudslides in Washington have made me realize more fully what it must have been like for the people here.  I cannot even imagine seeing a loved one simply disappear in a hole in the ground or washed away in a great wall of water.  I do not know how anyone could fully recover from such an experience, and my heart goes out to all who lost loved ones or experienced trauma.  Even though I did not share the experience or lose loved ones, I am very much a part of the community as we commemorate this devastating event.  Many of us are remembering the 1964 Good Friday earthquake by re-evaluating our personal preparations to survive the next big one.